Released: 26 Feb 2021

What if you had a time machine and went back to the 1960s? Will you help Agent 51 to solve crimes? Well now, you can do that in the new online slot game from Kalamba Games. The Agent 51 slot has one of the most unique themes we’ve seen so far which is the reason why it received many positive reviews. The base game plays out in cycles, where accumulated symbols expand on the 10th spin. This can lead you to payouts of up to 5,593x the stake. What’s more, the Agent 51 slot is based on the “Book of” mechanic, but it offers a completely different gameplay experience from the other games in this category. Find out more in our Agent 51 Slot Review.

Agent 51 Slot

Agent 51 Slot Online

Agent 51 is a new online slot from Kalamba Games that is part of the “Book of” series of slots. It has a plethora of features and extras including expanding symbols, multipliers, free spins, and a special feature in the base game that is triggered on every 10th spin. The game follows a special agent who tries to solve crimes in a top-secret facility filled with captured aliens. This highly-unique sci-fi themed slot machine can lead you to payouts that reach 5,593x your stake. Are you interested to learn more? Carry on reading our in-depth Agent 51 Slot Review!

About Agent 51 Slot

Kalamba Games succeeded in delivering a top-notch slot machine that combines secret agents and aliens in a facility that is placed somewhere in the mysterious Area 51. The game is called Agent 51 and plays out in cycles of 10 spins. We believe this is one of the most unique online slots that have been released in the past few months, and there’s a reason why. The Agent 51 slot is based on the “Book of” mechanic but it has completely different gameplay from other games like Book of Dead or Book of Ra Deluxe.

agent 51 slot

The Agent 51 slot plays on 5 reels, 3 rows, and 20 paylines. There, you have to take photos of the extraterrestrial creatures over a series of ten spins (we’ll explain this more below). This exciting slot machine can be played with bet levels that range anywhere from £0.50 and £50 per spin. Winning combinations are formed by landing 3 or more matching symbols across one of the 20 active paylines, starting from the leftmost reel.

This slot machine can be categorised into the group of sci-fi themed slots as well as the group of alien-themed slots. There, you’ll benefit from plenty of features, from expanding symbols to multipliers and free spins. All in all, you can win a maximum of 5,593x the stake. We’ll explain how to achieve these payouts below in our Agent 51 Slot Review.

Design, Symbols and Graphics

agent 51 slot paytable

The Agent 51 slot has a beautiful design with high-quality graphics. The base game plays out in what looks to be the Agent’s office, somewhere in the mysterious Area 51. The graphics are designed in a cartoonish format and they work pretty well in this game. The star of the show is the Agent himself, who has captured evidence of aliens such as images and footprints. Overall, it can be easily said that the Agent 51 slot provides a top-notch reel experience.

What’s even better in the Agent 51 slot is that Kalamba decided not to use the standard royal symbols as the low-paying ones. Instead, here we have five footprint symbols in blue, grey, dark brown, light brown, and yellow colours. These are accompanied by the higher-value symbols which are designed as blue, purple and orange aliens. The Agent himself is the wild symbol that substitutes for all regular symbols but also triggers the free spins feature. In addition, there are 2 other special symbols - the Polaroid camera and the UFO symbols, used in the bonus features.

RTP, Variance and Payouts for Agent 51 Slot

When it comes to the RTP of Agent 51, we’re glad that Kalamba Games built the game with an RTP of 96.17%, which is even better than the industry average of 96%. In addition, the game has a high variance, meaning that you’ll land less frequent but more valuable wins. In this slot, the top prize available is worth 5,593X your stake. If you want to learn more about RTP and variance models, read our detailed Variance, Volatility and RTP guide and see which one suits you best. 

Gameplay and Features on Agent 51 Slot

Agent 51 is a very exciting and innovative slot machine that has plenty to offer. There are a lot of things going on in this game and Kalamba Games managed to incorporate everything into two main features. One of the features is part of the base game and is called K-Loops, while the other is Free Spins. These come with many extras such as expanding symbols and multipliers, so let’s review them in more detail.


K-Loops is the most unique feature you’ll find in the Agent 51 slot, and it takes place in the base game. While you spin, you’ll notice that there are highlighted symbols above the reels. These symbols will transform into expanding symbols on every 10th spin. If you land the Polaroid accumulation symbol on an already highlighted symbol, you’ll receive a multiplier. 

Furthermore, the expanding symbol doesn’t need to land adjacent to the win when the 10th spin comes. But, to trigger it, you have to land at least 2 of the high-paying symbols anywhere on the reels, or at least 3 of the low-paying symbols. It’s possible to transform up to 7 symbols into expanding symbols which can lead you to huge base game payouts.

Free Spins Feature

Like in all “Book of” slots, there’s no scatter symbol, but the wild (or the book) acts as both wild and scatter. So, when you land at least 3 wild symbols on the reels in the Agent 51 slot, you will trigger the Free Spins feature. Then, you’ll receive 8 free spins to play with and a random symbol will be chosen to become expanding for the entire bonus. During the Free Spins feature, it’s also possible to land a UFO symbol which will give you 2 additional free spins. There’s no limit to how many free spins you can win.

Agent 51 Slot on Mobile

Agent 51 is built with HTML5 and it meets the latest technology standards. This means that the game is fully optimised for mobile and tablet use, so you can enjoy it on any mobile device and any operating system you have. You’ll receive the same high-quality gaming experience when you play the Agent 51 slot on mobile.

Other Kalamba Games Slots

Kalamba Games is an established slot provider that delivers high-quality and innovative games to the iGaming industry. As you can see from the Agent 51 slot, the provider knows how to create unique gaming experiences. So, if you’re looking for other Kalamba Games slots to try your luck at, you can check the Machina Megaways slot. It’s another sci-fi themed game where you’ll discover how to make androids. We would also recommend you to check the Atlantis Thunder slot that takes players on a diamond-shaped reel adventure under the sea. There, you’ll benefit from free spins, three jackpots and a hyper bonus. Or, you can try playing the Ruby Hunter slot and go on a treasure hunt with free spins and progressive jackpots.

SlotsWise Verdict

Agent 51 is a very modern-looking and enjoyable slot. The game is proof that “Book of” slots can be interesting, not boring. The K-Loops feature in the base game is very cool and it can take you to bigger payouts. It also means that you won’t need to worry about triggering the free spins feature in order to win big.

Play the Agent 51 slot and claim your welcome offer at one of our featured casinos.

Key Features
  • ProviderKalamba Games
  • Reels5
  • Min Bet0.50
  • Max Payout5593.00x
  • RTP96.17
  • Paylines20
  • Max Bet50.00
  • Bonus Rounds1
  • VarianceHigh
About The Author

Simona Boshkova


Simona is a writer with experience in the online gambling industry. She has reviewed and played plenty of online slots and knows how they work. In addition, she recognises the most important features in online slot games and always includes them in the reviews. Contact Simona

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